Stupid Scalp Psoriasis

I've been having problems with my scalp for a while now (o_O) my stupid ‪psoriasis has been playing up. I'm not sure if it has anything to do with stress or just the fact that it is now winter or maybe it's both.

So far changing my shampoo to a sulfate free one (see photo below) has done nothing to help, at least not yet but I was hoping to see a difference after using it for the past 9 days. Although my hair does look rather shiny (but it did look shiny with my last shampoo).

I now have a script for diprosone lotion, which used to be on the PBS but sadly isn't any more. I am a bit ticked off at the price I had to pay for this medication so it had better work. I recall using it many years ago but I can't remember whether it worked or not.

Is it too much to ask for nice skin? I've lived with this for nearly all of my life. For once I would like something to be 'normal'.

Sulfate free shampoo